Charles and Sarah lie silently. Charles feels horrified; everything he knows has been destroyed. He’s vaguely aware of the judgment of Ernestina and Mr. Freeman. He stares at the ceiling and pulls Sarah closer, and she takes his hand. They hear footsteps in the street, perhaps of a police officer. Charles says he’s worse than Varguennes. They can’t imagine what will happen to them. Charles comforts Sarah and says he has to break his engagement, but she says he doesn’t have to because it’s all her fault. He says he knew what to expect and ignored it, but Sarah says he wanted it to be like that. He strokes her hair.
As someone who has, up until now, lived more or less by society’s code, Charles has now acted in direct contradiction to everything that guides his world. He realizes that he’s acted like Varguennes, whom he has despised ever since hearing Sarah’s story. The police officer passing outside is a reminder of the social laws they’ve broken, and the punishment that’s sure to come.
Sarah says that Charles can’t marry her, but he says he must in order to preserve his self-respect. She retorts that her wickedness makes her unfit to be his wife. He would lose everything. But Charles says he doesn’t love Ernestina. Sarah says that she herself isn’t worthy of him. Charles starts to take her seriously and asks whether she really wants him to leave as though nothing happened. He can’t believe she would demand so little, but she says she can if she loves him. Charles is moved by her sacrifice. He despises male skepticism and selfishness, but he can’t help wondering if this could just be his last escapade before marriage. However, he knows he would feel horribly guilty if he deserted Sarah now.
Charles is still trying to obey social norms as much as he can, but duty could mean either following through with his engagement or marrying the woman whom he’s dishonored. He expects Sarah to want him to marry her, because that’s what women are supposed to want. He believes marriage would be her salvation because she’s “fallen.” Sarah, however, is driven by deeper desires. It’s unclear what her true motivations are, but her replies seem molded to appeal to Charles.
Sarah says she only wants Charles to be happy, and now she knows he has loved her, she can stand anything. Charles feels more connected to her than he’s ever felt to a woman. He kisses her and begins to feel aroused again, but he doesn’t believe that women can feel sexual pleasure, and he doesn’t want to take advantage of her any further. He sits up, saying he needs to think for a couple of days. She says again that she’s not worthy of him.
The fact that Fowles explicitly says that Charles doesn’t think women feel sexual pleasure sets the book apart from a Victorian novel, where this would be assumed factual knowledge. Now, when Charles is at the height of his trust in and connection to Sarah, he will discover that she’s not to be trusted after all.
Charles goes into the other room to dress and sees a red stain on his shirt. He suddenly realizes that he has just taken Sarah’s virginity. She lied about sleeping with Varguennes, and everything she did in Lyme was based in that lie. The only possible motivation is that she means to blackmail him. Charles is filled with horror as he imagines the female desire to take advantage of men and remembers the La Roncière case. He realizes Sarah is mad and evil, but he still can’t understand her. She appears in the doorway, and she can tell that he knows the truth.
Charles’s emotions reverse extremely quickly, and the reader is also surely astonished—this makes Sarah more mysterious than ever. In a culture where sex spells ruin for women, why would she choose to be seen as a fallen woman when it wasn’t even necessary—when she’s actually a virgin? And now she has made Charles into Varguennes by leading him to sleep with her. She has plotted to lose her virginity.
This time, Charles believes Sarah when she says she’s not worthy of him. She admits that when she went to the inn in Weymouth, she saw Varguennes with a prostitute, and she left before he saw her. Charles asks why she lied. She walks to the window and he realizes her ankle isn’t injured. She says she has deceived him, but she won’t bother him anymore. She seems defiant and says he has given her the strength to continue living because she can believe that if circumstances were different, they might have married. It’s true that she’s always loved him, but her loneliness fooled him. She can’t explain what she’s done. Charles refuses to accept this.
Like Varguennes, Charles, too, has tried to replace Sarah with a prostitute, though she doesn’t know it. The fact that Sarah has faked her ankle injury in order to make it necessary for Charles to come up to her room seems perhaps the most incriminating detail, because it proves such a high degree of premeditated manipulation. It’s possible that Sarah is truly a mystery even to herself. What’s clear is that she doesn’t need Charles, but only the knowledge of her own worth that he gives her.
Sarah tells Charles to leave, but he doesn’t. She sees his worry in his face and says that she’s very strong, and will only die by natural causes. Charles moves to go, saying bitterly that his reward for all the risks he’s taken is to learn that he’s been fooled. Sarah says he could never be happy with her. He insists that he just wants to understand, but she orders him to leave. Finally, he does.
In a way, Charles becomes a proxy for the reader here, begging to understand the story that is Sarah. Besides, the reader schooled in Victorian literature will know that fallen women often kill themselves in a sort of narrative punishment, so the reader, too, might think Sarah will end in suicide.